Segment Information - Schedule of Financial Information for Reportable Segments (Details) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($) segment	Jun. 30, 2023 USD ($)	Nov. 30, 2023
Segment Reporting [Abstract]
Number of reportable segments | segment			3
Segment Reporting Information [Line Items]
Net sales	$ 3,716	$ 4,055	$ 11,126	$ 11,666
Adjusted EBITDA	202	276	645	703
Corporate-related costs	0	0	(6)	0
Restructuring and impairment costs	(16)	(6)	(152)	(30)
Purchase accounting amortization	(12)	(13)	(36)	(39)
Restructuring related charges	(4)	(3)	3	(6)
Impairment of interests in nonconsolidated partially owned affiliates	0	0	0	(6)
Depreciation	(71)	(74)	(213)	(214)
Equity based compensation	(5)	(7)	(28)	(25)
Earnings before interest and income taxes	94	173	213	383
Net financing charges	(48)	(49)	(139)	(149)
Other pension expense	(1)	(1)	(5)	(12)
Income before income taxes	45	123	69	222
Gain on contract settlement			3	1
Stock based compensation	5	7	28	25
Recorded charges	1		1
One-time divestiture related tax impact at an affiliate			1
Net actuarial and settlement/curtailment (gain) loss	0	0	0	8
Adient (Langfang) Seating Co., Ltd | Disposed of By Sale
Segment Reporting Information [Line Items]
Loss on disposal			8
Subsidiary, ownership percentage disposed					51.00%
Restatement Adjustment
Segment Reporting Information [Line Items]
Equity based compensation			(5)
Stock based compensation			5
Americas
Segment Reporting Information [Line Items]
Net sales	1,737	1,900	5,044	5,385
Gain on disposition of property plant equipment			10
Brazil
Segment Reporting Information [Line Items]
One-time gain			1
Americas
Segment Reporting Information [Line Items]
Net actuarial and settlement/curtailment (gain) loss				8
EMEA
Segment Reporting Information [Line Items]
Impairment of nonconsolidated partially owned affiliates				3
Asia
Segment Reporting Information [Line Items]
Impairment of nonconsolidated partially owned affiliates				4
Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA	225	298	713	771
Operating Segments | Americas
Segment Reporting Information [Line Items]
Net sales	1,737	1,900	5,044	5,385
Adjusted EBITDA	99	95	259	236
Operating Segments | EMEA
Segment Reporting Information [Line Items]
Net sales	1,288	1,438	3,926	4,021
Adjusted EBITDA	25	103	127	184
Operating Segments | Asia
Segment Reporting Information [Line Items]
Net sales	712	742	2,224	2,337
Adjusted EBITDA	101	100	327	351
Corporate/Eliminations
Segment Reporting Information [Line Items]
Net sales	(21)	(25)	(68)	(77)
Adjusted EBITDA	(23)	(22)	(68)	(68)
Corporate-related costs	$ (23)	$ (22)	$ (68)	$ (68)